Method of inhibiting deterioration of organic compounds



Patented July 19, 1949 METHOD OF INHIBITING DETERIORATION OF ORGANIC COMPOUNDS Bert E. Lincoln, Ponca City, Okla., and Clarence A. Nellson, Linthicum Heights, Md., assignors to Continental Oil Company, PoncaCity, kla., a corporation of Delaware No Drawing. Application April 28, 1944, Serial No. 533,254

4 Claims. 1

Our invention relates to a method of protecting and inhibiting oxygen containing organic compounds against discoloration or other deleterious changes during halogenation thereof in the presence of iron or iron compounds.

This is a continuation-in-part of our copending application, Serial No. 384,414, filed March 20, 1941, which matured into Patent No. 2,370,552 on the 27th day of February 1945.

When dry oxygen containing organic compounds are halogenated at elevated temperatures in glass equipment, their color remains practically unchanged. At least, they never become darker than the halogen bearing compound should be. However, when the halogenation process is carried out in equipment having iron exposed to the reaction mixture or in the presence of traces of water and iron or iron compounds such as iron chlorides, the halogenated compounds immediately become black and may undergo other objectionable changes in a short period of time. Such materials are useless in their changed state, and restoration to their original condition is very difllcult and expensive it not impossible.

An important object of our invention is to provide a method of preventing deterioration of oxygen containing organic materials during halogenation thereof.

Another object of our invention is to prevent the discoloration of oxygen containing organic compounds by halogenation thereof in the presence of water and iron or iron compounds.

A further object or our invention is to provide an improved method of halogenating oxygen containing organic materials in ferrous equipment.

Other objects and advantages of our invention will appear in the course of the following description.

We have found that the addition of a small amount of various basic nitrogenous organic compounds to the material undergoing halogenation will greatly. inhibit or entirely prevent the discoloration and deterioration of the organic materials although large quantities of moisture, iron, and iron chlorides are present. The nitrogenous organic compounds are preferably mixed with the material to be halogenated before the where B may be an alkyl. alkylol, aryl, aralkyl,

'2 hydroaryl, or heterocycllc radical and R and R" may be hydrogen, hydroxyl, alkyl. alkylol, aryl, aralkyl, hydroaryl, or heterocyclic radicals. These amines may be either oil or water-soluble. Heterocyclic nitrogen compounds are also suitable. Specific examples of the compounds which may be used are:

I. Aliphatic amines Amylamine Diamylamine Triamylamine Tributylamine Cetylamine Ethanolamine Diethanolamine Triethanolamine Propanolamine 10. Ethylenediamine l1. Propylenediamine 12; Diethylenetriamine 13;. Triethylenetetramine 14. 'I'etraethylenepentamine II. Aromatic Amines 1. Aniline 2. Methylaniline 3. Dimethylaniline 4.- Diamylanillne 5. Toluidine 6. Xylidine '7. Diphenylamine 8. Triphenylamine 9. Nitraniline 10. Phenylene diamine 11. Aminophenol 12. Aminodiphenyl 13. Benzidine 1.4. Benzamide 15 Acetanilide 16. Acet-toluidide 17. Acetoacetanilide lII. Heterocyclic Amines. and Nitrogen Bases 1. Pyridine 2. Pyrrol 3. Pyl'rolidine 4. Piperidine 5. Lutidine 6. Aminobenzofurane '7. Morpholine 8. Benzimidazol 9. Carbazol 10. Nicotinic acid 11. Picollne 12. Brucine Any of the above, mixtures of the above or various oxygen, halogen, nitrogen, sulfur, or

phosphorus derivatives of these compounds may be used within the scope of our invention.

Amounts in the order of from 0.05 to 1 or 2 per cent of the amines are added, based on the amount of material to be halogenated. Some of the more effective nitrogen compounds, however, may be required in smaller amounts and we may use as much as 5 or per cent of some of the amines.

The following examples of applications of our invention are intended to be illustrative only and are not to be construed as limitations.

Example 1 Example 2 Upon chlorinating stearic acid in ferrous equip ment, the product became extremely black when less than 4 per cent of chlorine had been introduced into the stearic acid. Repeating the experiment but introducing .5 per cent of diethanolamine in the stearic acid permitted chlorinating the stearic acid to approximately 17 per cent total chlorine content, with a finished true color of 3.

Example 3 Upon chlorinating diphenyl-oxide in ferrous equipment, the product darkened to a true color of approximately 500. Repeating the experiment but using .5 per cent of triamylamine based upon a total weight of diphenyloxide, we were able to chlorinate the material to a chlorine content of 20 per cent, with a finished true color of 4.

Experiments similar to examples above have been conducted with other oxygen bearing organic compounds with outstandingly good results. Oxygen bearing organic compounds of open chain, closed chain, and of heterocyclic character are included within the scope of our invention. Some of these compounds are:

Aliphatic alcohols H butyl alcohol isobutyl alcohol tertiary butyl alcohol amyl alcohol isoamyl alcohol pentanol 2 hexanol hexanol 3 diisopropylcarbinol lauryl alcohol octyl alcohol carnaubyl alcohol ceryl alcohol methyl vinyl carbinol propargyl alcohol glycol glycerol erythritol vinyl alcohol allyl alcohol Carbocyclic alcohols cyclobutanol cyclohexanol methyl cyclohexanol tertiary butyl cyclohexanol cyclohexandiol 1, 4 cyclopentanol methyl cyclopentanol Phenols phenol ortho cresol meta cresol para cresol xylenols ethyl phenol mesitol para tertiary butyl phenol thymol wax substituted phenol Aromatic alcohols benzyl alcohol phenyl methyl carbinol tolyl carbinol 2, 4 dimethyl benzyl alcohol Aliphatic esters methyl stearate methyl oleate oleyl acetate stearyl acetate ethyl acetate methyl butyrate hexyl acetate glycol stearate glyceryl oleate dibutyl malonate dipropyl succinate mono methyl malonate Aromatic esters phenyl benzoate benzyl benzoate tolyl benzoate butyl phthalate phenyl sulfonate phenyl naphthenate methyl benzoate stearyl benzoate phenyl ester of phenyl acetic acid Aliphatic ketones vinyl methyl ketone mesityl oxide phorone methyl heptanone stearone laurone ethylidene acetone Cyclic ketones acetophenone benzophenone cyclohexanone propiophenone triethylacetophenone Aldehydes, aliphatic and cyclic methylethyl acetaldehyde valeraldehyde isobutyraldehyde caprylic aldehyde salicylaldehyde anisaldehyde vanillin safrole Ethers, aliphatic and aromatic n-propyl ethers isopropyl ethers methyl tertiary butyl ether Ethers, aliphatic and aromatic-Continued cetyl ether isoamyl ether diphenyl ether dibenzyl ether diphenylene oxide ditolyl ether phenyl methyl ether Nitro compounds nitro ethane nitro butane nitropentane nitrobenzene dinitrobenzene nitrophenol o-nitrotoluol m-nitrotoluol p-nitrotoluol nitro xylol nitropseudocumol nitromesltyline After chlorination, the oils are washed with a dilute solution of sodium carbonate to remove free hydrochloric acid. This treatment also serves to remove the amine hydrochlorides and any remaining free amines.

The emcacy of the amines in preserving the color of oxygen containing organic material during chlorination is probably due in part to their being adsorbed on exposed iron surfaces and thereby inhibiting theaction of hydrochloric acid on the iron, tending to form ferric chloride. Evidently the color deterioration of the compounds is associated with the formation of iron chlorides, for such organic oxygen compounds chlorinated in the presence of iron chlorides without amines rapidly lose color.

In addition to the foregoing, the amines have another very desirable property of preventing color increase in organic compounds being chlorinated when iron chloride as such is known to be present. We do not know why the amines are still eflective in preserving color in the presence of iron chloride, but broad experience has taught us that the amines inhibit some color-forming reaction.

The presence 1f amines in the halogenation mixture therefore serves the double purpose of inhibiting the attack of hydrochloric acid on the iron reaction vessels and preventing color loss by the oils undergoing chlorination.

Speculations and theories as to the reason for the results obtained are but conjectures as to what probably occurs. and we do not wish to be bound by them except in so far as they are compatible with the truth.

While chlorine and chlorination are specifically referred to, we contemplate the application of our invention in all halogenation processes, regardless of the halogen employed. Brominations, particularly, as well as i'luorinations and iodinations may be subjected to the improvements of our invention.

In the appended claims where reference is made to iron, we-intend to include not only elemental iron but also compounds of iron.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of our claims. It is further obvious that various changes may be made in details within the scope of our claims without departing from the spirit of our invention. It is therefore to be understood that our invention is not to be limited to the specific details shown and described.

Having thus described our invention, we claim:

1. The method of inhibiting discoloration and deterioration of ethers during chlorination thereof in the presence of iron which comprises adding to the' chlorination mixture from about 0.5% to about 2% of an amine.

2. The method of inhibiting discoloration and deterioration of esters during chlorination thereof in the presence of iron which comprises adding to the chlorination mixture from about .05% to about 2% of an amine.

3. The method of inhibiting discoloration and deterioration of organic acids during chlorination thereof in the presence of iron which comprises adding to the chlorination mixture from about .05% to about 2% of an amine.

4. The method of inhibiting discoloration and deterioration of non-acidic organic oxygen compounds during chlorination thereof in the presence of iron which comprises adding to the chlorination mixture fromabout .05% to about 2% of an amine. I

BERT H. LINCOLN. CLARENCE A. NEILSON.

REFERENCES crrap The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,679,998 Voltz Aug. '1, .1928 is 1,890,099 Smith et al. Dec. 6, 1932 an iigertificate of Correction Patent No. 2,476,554. July 19, 1949. BERT H. LINCOLN ET AL. It is hereby certified that error appears in the printed specification o'ftii above numbered patent requiring correction as follows: Column 6, line 26, claim 1, for 0.5% read 05%;

and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

' Signed and sealed this 6th day of December, A. D. 1949.

THOMAS F. MURPHY,

Assistant Commissioner of Patents. 

